Why do you think other government/country want to use an English abbreviation for their government entities ? Even for Latin language that use a similar word "gouv" (french), "gob" (spanish) or "guv" (romanian) would be more natural.
Various government departments of those countries use domains under .gouv.fr, .gob.es, .gov.ro respectively. The argument is that fairness and clarity would suggest that the US likewise use .gov.us or some other convention of their choice under .us.